Self-adjusting caster.



I'. G. LUCE. SELF DJUSTING GASTEBg APPLIOATIQH FILED APB. 9, 1909,

attorney A Swihmaaeo C. LUCE, OF IDALTN, MASSACHUSETTS, ASSIGNOR T0 LUCE MANUFACTUJ'" COMPANY, @E DALIGN, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

snnr-smus'rrns CASTER.

Specification of Letters Patent. Patented Isl-0V. 23

Application fxledprl 9, 1909. Serial No. 488,836.

ffl

`o all whom it may conservi: l

lle 1t known that l', THOMAS C.. LUCE, a

citizen o-the United States, residing at Dale suon es .e table or a chair leg, or any/ which it is desired shall eutoseit to varying dision has particular reference to ibling `ble or chair, or other ta 'rniture l having a plurality of door so that'no the bottom of as often occurs l s especially designed e '..ot niece for e. telf re ling aloeering, on it nivsel to an A en ofniistruoted a' it is equally applicable for use uliont a roller or wheel to bear on the otlir; pierresr the tollf 1. ir? L to the v uen tlie invention consists in. the soinhination of parts substantially hereinafter described and Yclaimed.

@t the aeoornpsnying drawings z-Fgure is a side elevation et my invention emliedied in the form of a caster, the same seing attached to the lower end of a table l s, the ter being partly in section. Fig. l view similar to Fig. 1, and in a different automatically on. represents a 4seeo Fig. 1., Fig. e is an ievf of tl e device above the line Fig. 5 is a view sirnilarto a portion of Fig. 1, but illustrating the device as a leg support'having no roller or Wheel. Fig, 6 is a view similar to F ig. 2, but illus trating a modification hereinafter described.

Similar reference characters indicate 'the saine vor similar parts in all of the views.

Referring first to the structures shown in Figs. 1 to f1, 10 denotes the lower end furniture leg, such as a table leg, but it is to be understood that this term is used for 'the purpose of illustration 'and not of limitation. The leg 10 is formed with a vertical bore 11 such as is commonly employed to' receive the upper portion of an ordinary easter.

M-y improved attachment in the einhodi ment illustrated comprises upper and lower disks 12 and 13, the upper one being :formed with a. sleeve portion 14 which 'Clos fils the' bore 11 in the leg 10, the d# ing a cone-shaped 15 flange 16; The lower disk 13 as to 'form between its upper face and lower face 15 of the disk 12 a conoav -eonn veX spncen `The angle of coneavity face of the disk relatively to the the cone of the upperdislf; suoli th space between the opposing faces of e u disks gradually increases from the center 'to the periphery.

The disk 13 is secured to a stem 17 so to rotate. therewith, although this is a solutely essential, that is, it is not essenU` that the stein 17 shall rotate. 1t is esse t' ffl however that one of the disks shall be itrue to rotate relatively to the other 'for a reason hereinafter described. The disk 13 may he formed integral with or rigidly seouret. to a sleeve 18 which is screwed on or otherwise secured to the lowerV end ofthe stem, sjfvid limit the lowermost position which the concave disk may assume away from the conefaced disk 12. l

The flange or rim 16 preferably extends down, to overlap the outer edge of the 13 when the latter isin its lowest po radial ouideways forthe balls 24, said guide-ways permitting the balls to move or roll radially ofthe spacer.

.It will now be readily understood when the parts are in the position shown in Fig. 2, if the particular table or chair leg to which the device is applied, is over an uneven portion of the flooring which would not positively support the wheel, the said wheel and x stem 17 and vthe lower disklwill drop to the'l 4,extent which may be permitted ,by the stop 23, .or which ma be permitted by the amount of depression of that particular portion of the 'liooring This of course permits the balls 24 to roll inward and since the annular space between the faces of the two disks gradually contracts toward the center, the balls 26 roll inward as far as they may be free to move, and theyimmediately act to lock the parts with the disks just so far separated according to the distance which the lower disk has moved. No amount of pressure will force the balls outward unless -V something occurs to cause them to rolllat-.

emily. Any lateral move/ment of the leg A10 in any such direction as 'toca-use the caster or wheel-arms 19 t6 swing around, will rotate the lower' disk 13 so that the balls are vrallcd laterally or around the cone 15. Doivnward pressure of tuel cone exerted at the same time crowds the balls up the inoline just so far as they may be pushed by the lower disk and they will remain at that point 'and oppose further upward movement unless the disk 13 is again rotated. If pushed npward .too far and the caster-- whe-e121 should be gradually moved to a position-over a depression in 'the flooring, 'said Wheel` and ,the stem and the loweridisk will again descend and theJ balls roll inward and look the two disks apart. t

As shown in Fig. 5, the caster-wheel vmay be omitted, and instead ot' arms 19, there may be provided a foot 27 extending laterally from the lower end of the stem 17 to bear on the wheel.

'--As shown in Fig. 6, instead of thev lower floor substantially as a caster disk beingconcave it may be convex or coneshaped as indicated at 131, and the upper disk 121 may have a concave lower face. In this case-.the balls 240 wouldv sim ly ro'll outward instead of. inward when t e stem 171 dro s, and would be Icrowded inward instead o outward when there is a rotation of one disk relatively to the other and'under pressure.

Having lnow described my invention, I claim: r

1. A self-locking support comprising two members having opposing faces which are inclined at4 different angles to form' a tapering space betweenthelmone of said members being movable relatively to the other to vary .the width of said space, and a rolling member'in said space free to move in the direction in which said space tapers. 2. A' self-locking support comprising two disks facinv each other ,and having their faces at dierent anglesto a plane transverse tothe axis of the disks, and rolling members free to move in any direction between said faces.

3. A self-locking support comprising two'y disks facino' each otherand having their faces at ditbferent angles to a pla e transverse to the axis of vthe disks, an rolling members free to move in any direction between said faces, means being provided for holding said rolling members spaced apart.

4. An automatic length adjuster for the purposes described, comprising a pair of" andballsmounted in said space and free to move around the'space or toward and from i the center thereof.

lIn testimony whereof I affix my signature in presence of two witnesses.

THOMAS C. LUCE. Witnesses:

W. M. DELAVAN, J. B. VVooDBURN. 

